..The present study tested the hypothesis that both concern for others and active disregard for others in distress in toddlers and young children predict antisocial behavior during middle childhood and adolescence...

The validity of analyses testing the etiology of comorbidity between two disorders: comparisons of disorder prevalences in families

..Discrepancies in results may reflect different analytical approaches or differences in the samples. Here, we examine the causes of comorbidity between alcohol dependence and illicit drug dependence in adolescents...

..The ability to distinguish the correct model decreased as the sample size and the correlation between the underlying deficits and the symptom scores decreased, suggesting that the issue of power should be considered carefully...

Early childhood temperament and the covariation between internalizing and externalizing behavior in school-aged children

..A possible limitation of this study is that the covariation between temperament and behavior problems may be due to shared measurement variance, as parent ratings were used to assess both temperament and behavior problems...

Test of alternative hypotheses explaining the comorbidity between attention-deficit/hyperactivity disorder and conduct disorder

..Unfortunately, the conclusions of family studies using these two methods have been conflicting. In the present study, we examined the validity of family prevalence analyses in testing alternative comorbidity models...

Etiology of sex differences in the prevalence of ADHD: an examination of inattention and hyperactivity-impulsivity

..This evidence for the PMT model and against the CV model was found for both inattention and hyperactivity-impulsivity, but became weaker for hyperactivity-impulsivity as symptom severity increased...

The validity of the Neale and Kendler model-fitting approach in examining the etiology of comorbidity

..As suggested by Neale and Kendler, the model-fitting approach can be applied to both unselected and selected data and to both twin and family data...

Genetic and environmental influences on substance initiation, use, and problem use in adolescents

Soo Hyun RheeDepartment of Psychology and the Institute for Behavioral Genetics, University of Colorado at Boulder, 90309, USAArch Gen Psychiatry 60:1256-64. 2003

..We conducted a sibling/twin/adoption study of substance initiation, use, and problem use, estimating the relative contribution of genetic and environmental influences on these phenotypes in adolescents...

The neuronal nicotinic receptor subunit genes (CHRNA6 and CHRNB3) are associated with subjective responses to tobacco

..Our results suggest that some genetic factors will increase an individual's vulnerability to both MDD and CD in adolescence...

Examining the heritability of a laboratory-based smoking endophenotype: initial results from an experimental twin study

Lara A RayDepartment of Psychology and Institute for Behavioral Genetics, University of Colorado, Boulder, Colorado, United States of AmericaTwin Res Hum Genet 10:546-53. 2007

..To the best of our knowledge, this is the first study to examine the genetic basis of a laboratory smoking endophenotype, in this case tension reduction after smoking. Implications for genetic association studies are discussed...

..The magnitudes of both shared and non-shared environmental influences were negligible among those who perceived their peers to be least delinquent and were greater among those with higher levels of perceived peers' delinquency...

Bivariate analysis of disordered eating characteristics in adolescence and young adulthood

..different levels of severity of substance involvement, to what degree do each of the 11 abuse and dependence criteria assess adolescent cannabis problems, and do the DSM-IV items function similarly across different adolescent populations?..

Subjective effects to marijuana associated with marijuana use in community and clinical subjects

..e. subjective effects). We have examined subjective effects in adolescent, young adult community, and clinical populations to determine how patterns of use may be predicted by an individual's subjective experiences with the drug...

Case-control and within-family tests for an association between conduct disorder and DAT1

..Results were more consistent with the hypothesis that parents respond to children's genetically-influenced conduct problems by maltreating them than the hypothesis that maltreatment causes conduct problems...

..This paper describes the result of an investigation of the extent to which comorbid alcohol and illicit drug dependence in adolescents are explained by etiological factors in common with conduct disorder...

..This study provides the first evidence for association between the CHRNB2 gene and nicotine- and alcohol-related phenotypes, and suggests that polymorphisms in CHRNB2 may be important in mediating early responses to nicotine and alcohol...

..We first tested for changes in alcohol consumption in adolescents who did and did not subsequently attend college, and then tested for variation of the genetic and environmental determinants of drinking in these 2 groups...

..Genetic risk factors account for part of the variation in the development of cannabis dependence symptoms; however, no linkage studies have been performed for cannabis dependence symptoms. This study aimed to identify such loci...

Comorbidity of depression with levels of smoking: an exploration of the shared familial risk hypothesis

..The conflicting findings of the studies that have examined the relationship between smoking and depression may be attributable to differences in definition of the disorders and the methods used to analyze them...